51
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Márquez S, Fernández JJ, Terán-Cabanillas E, Herrero C, Alonso S, Azogil A, Montero O, Iwawaki T, Cubillos-Ruiz JR, Fernández N, Crespo MS. Endoplasmic Reticulum Stress Sensor IRE1α Enhances IL-23 Expression by Human Dendritic Cells. Front Immunol 2017; 8:639. [PMID: 28674530 PMCID: PMC5475432 DOI: 10.3389/fimmu.2017.00639] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/16/2017] [Indexed: 12/31/2022] Open
Abstract
Human monocyte-derived dendritic cells (DCs) exposed to pathogen-associated molecular patterns (PAMPs) undergo bioenergetic changes that influence the immune response. We found that stimulation with PAMPs enhanced glycolysis in DCs, whereas oxidative phosphorylation remained unaltered. Glucose starvation and the hexokinase inhibitor 2-deoxy-d-glucose (2-DG) modulated cytokine expression in stimulated DCs. Strikingly, IL23A was markedly induced upon 2-DG treatment, but not during glucose deprivation. Since 2-DG can also rapidly inhibit protein N-glycosylation, we postulated that this compound could induce IL-23 in DCs via activation of the endoplasmic reticulum (ER) stress response. Indeed, stimulation of DCs with PAMPs in the presence of 2-DG robustly activated inositol-requiring protein 1α (IRE1α) signaling and to a lesser extent the PERK arm of the unfolded protein response. Additional ER stressors such as tunicamycin and thapsigargin also promoted IL-23 expression by PAMP-stimulated DCs. Pharmacological, biochemical, and genetic analyses using conditional knockout mice revealed that IL-23 induction in ER stressed DCs stimulated with PAMPs was IRE1α/X-box binding protein 1-dependent upon zymosan stimulation. Interestingly, we further evidenced PERK-mediated and CAAT/enhancer-binding protein β-dependent trans-activation of IL23A upon lipopolysaccharide treatment. Our findings uncover that the ER stress response can potently modulate cytokine expression in PAMP-stimulated human DCs.
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Affiliation(s)
- Saioa Márquez
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valladolid, Valladolid, Spain
| | - José Javier Fernández
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valladolid, Valladolid, Spain
| | - Eli Terán-Cabanillas
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, United States.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medical College, New York, NY, United States.,Unidad Académica de Ciencias de la Nutrición y Gastronomía, Universidad Autónoma de Sinaloa, Culiacán, México
| | - Carmen Herrero
- Instituto de Biología y Genética Molecular, CSIC-Universidad de Valladolid, Valladolid, Spain
| | - Sara Alonso
- Instituto de Biología y Genética Molecular, CSIC-Universidad de Valladolid, Valladolid, Spain
| | - Alicia Azogil
- Instituto de Biología y Genética Molecular, CSIC-Universidad de Valladolid, Valladolid, Spain
| | - Olimpio Montero
- Centro para el Desarrollo de la Biotecnología, CSIC, Parque Tecnológico de Boecillo, Valladolid, Spain
| | - Takao Iwawaki
- Division of Cell Medicine, Medical Research Institute, Kazanawa Medical University, Ishikawa, Japan
| | - Juan R Cubillos-Ruiz
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, United States.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medical College, New York, NY, United States
| | - Nieves Fernández
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valladolid, Valladolid, Spain.,Instituto de Biología y Genética Molecular, CSIC-Universidad de Valladolid, Valladolid, Spain
| | - Mariano Sánchez Crespo
- Instituto de Biología y Genética Molecular, CSIC-Universidad de Valladolid, Valladolid, Spain
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Pettit AP, Jonsson WO, Bargoud AR, Mirek ET, Peelor FF, Wang Y, Gettys TW, Kimball SR, Miller BF, Hamilton KL, Wek RC, Anthony TG. Dietary Methionine Restriction Regulates Liver Protein Synthesis and Gene Expression Independently of Eukaryotic Initiation Factor 2 Phosphorylation in Mice. J Nutr 2017; 147:1031-1040. [PMID: 28446632 PMCID: PMC5443467 DOI: 10.3945/jn.116.246710] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/20/2017] [Accepted: 03/15/2017] [Indexed: 01/12/2023] Open
Abstract
Background: The phosphorylation of eukaryotic initiation factor 2 (p-eIF2) during dietary amino acid insufficiency reduces protein synthesis and alters gene expression via the integrated stress response (ISR).Objective: We explored whether a Met-restricted (MR) diet activates the ISR to reduce body fat and regulate protein balance.Methods: Male and female mice aged 3-6 mo with either whole-body deletion of general control nonderepressible 2 (Gcn2) or liver-specific deletion of protein kinase R-like endoplasmic reticulum kinase (Perk) alongside wild-type or floxed control mice were fed an obesogenic diet sufficient in Met (0.86%) or an MR (0.12% Met) diet for ≤5 wk. Ala enrichment with deuterium was measured to calculate protein synthesis rates. The guanine nucleotide exchange factor activity of eIF2B was measured alongside p-eIF2 and hepatic mRNA expression levels at 2 d and 5 wk. Metabolic phenotyping was conducted at 4 wk, and body composition was measured throughout. Results were evaluated with the use of ANOVA (P < 0.05).Results: Feeding an MR diet for 2 d did not increase hepatic p-eIF2 or reduce eIF2B activity in wild-type or Gcn2-/- mice, yet many genes transcriptionally regulated by the ISR were altered in both strains in the same direction and amplitude. Feeding an MR diet for 5 wk increased p-eIF2 and reduced eIF2B activity in wild-type but not Gcn2-/- mice, yet ISR-regulated genes altered in both strains similarly. Furthermore, the MR diet reduced mixed and cytosolic but not mitochondrial protein synthesis in both the liver and skeletal muscle regardless of Gcn2 status. Despite the similarities between strains, the MR diet did not increase energy expenditure or reduce body fat in Gcn2-/- mice. Finally, feeding the MR diet to mice with Perk deleted in the liver increased hepatic p-eIF2 and altered body composition similar to floxed controls.Conclusions: Hepatic activation of the ISR resulting from an MR diet does not require p-eIF2. Gcn2 status influences body fat loss but not protein balance when Met is restricted.
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Affiliation(s)
- Ashley P Pettit
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - William O Jonsson
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Albert R Bargoud
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Emily T Mirek
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Frederick F Peelor
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Yongping Wang
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ
| | - Thomas W Gettys
- Laboratory of Nutrient Sensing and Adipocyte Signaling, Pennington Biomedical Research Center, Baton Rouge, LA
| | - Scot R Kimball
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey PA; and
| | - Benjamin F Miller
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Karyn L Hamilton
- Department of Health and Exercise Science, Colorado State University, Fort Collins, CO
| | - Ronald C Wek
- Department of Biochemistry of Molecular Biology, Indiana University School of Medicine, Indianapolis, IN
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ;
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53
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Endoplasmic reticulum stress and unfolded protein response in infection by intracellular parasites. Future Sci OA 2017; 3:FSO198. [PMID: 28883998 PMCID: PMC5583660 DOI: 10.4155/fsoa-2017-0020] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 03/21/2017] [Indexed: 12/30/2022] Open
Abstract
Perturbations of the physiological status of the endoplasmic reticulum (ER) trigger a specific response known as the ER stress response or unfolded protein response (UPR). In mammalian cells, the UPR is mediated by three ER transmembrane proteins (IRE1, PERK and ATF6) which activate three signaling cascades to restore ER homeostasis. In recent years, a cross-talk between UPR, inflammatory and microbial sensing pathways has been elucidated. Pathogen infection can lead to UPR activation; moreover, several pathogens subvert the UPR to promote their survival and replication. While the UPR in viral and bacterial infection has been characterized, little is known about the role of UPR in intracellular parasite infection. Here, we review recent findings on UPR induction/modulation by intracellular parasites in host cells.
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54
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Ariyasu D, Yoshida H, Hasegawa Y. Endoplasmic Reticulum (ER) Stress and Endocrine Disorders. Int J Mol Sci 2017; 18:ijms18020382. [PMID: 28208663 PMCID: PMC5343917 DOI: 10.3390/ijms18020382] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 01/24/2017] [Accepted: 02/03/2017] [Indexed: 12/15/2022] Open
Abstract
The endoplasmic reticulum (ER) is the organelle where secretory and membrane proteins are synthesized and folded. Unfolded proteins that are retained within the ER can cause ER stress. Eukaryotic cells have a defense system called the “unfolded protein response” (UPR), which protects cells from ER stress. Cells undergo apoptosis when ER stress exceeds the capacity of the UPR, which has been revealed to cause human diseases. Although neurodegenerative diseases are well-known ER stress-related diseases, it has been discovered that endocrine diseases are also related to ER stress. In this review, we focus on ER stress-related human endocrine disorders. In addition to diabetes mellitus, which is well characterized, several relatively rare genetic disorders such as familial neurohypophyseal diabetes insipidus (FNDI), Wolfram syndrome, and isolated growth hormone deficiency type II (IGHD2) are discussed in this article.
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Affiliation(s)
- Daisuke Ariyasu
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan.
| | - Hiderou Yoshida
- Department of Biochemistry and Molecular Biology, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan.
| | - Yukihiro Hasegawa
- Division of Endocrinology and Metabolism, Tokyo Metropolitan Children's Medical Center, Tokyo 183-8561, Japan.
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55
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Ribeiro CMP, Lubamba BA. Role of IRE1α/XBP-1 in Cystic Fibrosis Airway Inflammation. Int J Mol Sci 2017; 18:ijms18010118. [PMID: 28075361 PMCID: PMC5297752 DOI: 10.3390/ijms18010118] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 12/13/2022] Open
Abstract
Cystic fibrosis (CF) pulmonary disease is characterized by chronic airway infection and inflammation. The infectious and inflamed CF airway environment impacts on the innate defense of airway epithelia and airway macrophages. The CF airway milieu induces an adaptation in these cells characterized by increased basal inflammation and a robust inflammatory response to inflammatory mediators. Recent studies have indicated that these responses depend on activation of the unfolded protein response (UPR). This review discusses the contribution of airway epithelia and airway macrophages to CF airway inflammatory responses and specifically highlights the functional importance of the UPR pathway mediated by IRE1/XBP-1 in these processes. These findings suggest that targeting the IRE1/XBP-1 UPR pathway may be a therapeutic strategy for CF airway disease.
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Affiliation(s)
- Carla M P Ribeiro
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
- Department of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Bob A Lubamba
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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56
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Navid F, Colbert RA. Causes and consequences of endoplasmic reticulum stress in rheumatic disease. Nat Rev Rheumatol 2016; 13:25-40. [PMID: 27904144 DOI: 10.1038/nrrheum.2016.192] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Rheumatic diseases represent a heterogeneous group of inflammatory conditions, many of which involve chronic activation of both innate and adaptive immune responses by multiple genetic and environmental factors. These immune responses involve the secretion of excessive amounts of cytokines and other signalling mediators by activated immune cells. The endoplasmic reticulum (ER) is the cellular organelle that directs the folding, processing and trafficking of membrane-bound and secreted proteins, including many key components of the immune response. Maintaining homeostasis in the ER is critical to cell function and survival. Consequently, elaborate mechanisms have evolved to sense and respond to ER stress through three main signalling pathways that together comprise the unfolded protein response (UPR). Activation of the UPR can rapidly resolve the accumulation of misfolded proteins, direct permanent changes in the size and function of cells during differentiation, and critically influence the immune response and inflammation. Recognition of the importance of ER stress and UPR signalling pathways in normal and dysregulated immune responses has greatly increased in the past few years. This Review discusses several settings in which ER stress contributes to the pathogenesis of rheumatic diseases and considers some of the therapeutic opportunities that these discoveries provide.
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Affiliation(s)
- Fatemeh Navid
- Pediatric Translational Research Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Building 10, Room 12N248B,10 Center Drive, Bethesda, Maryland 20892, USA
| | - Robert A Colbert
- Pediatric Translational Research Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Building 10, Room 12N248B,10 Center Drive, Bethesda, Maryland 20892, USA
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57
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Moretti J, Blander JM. Cell-autonomous stress responses in innate immunity. J Leukoc Biol 2016; 101:77-86. [PMID: 27733577 DOI: 10.1189/jlb.2mr0416-201r] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 08/10/2016] [Accepted: 08/24/2016] [Indexed: 12/12/2022] Open
Abstract
The innate immune response of phagocytes to microbes has long been known to depend on the core signaling cascades downstream of pattern recognition receptors (PRRs), which lead to expression and production of inflammatory cytokines that counteract infection and induce adaptive immunity. Cell-autonomous responses have recently emerged as important mechanisms of innate immunity. Either IFN-inducible or constitutive, these processes aim to guarantee cell homeostasis but have also been shown to modulate innate immune response to microbes and production of inflammatory cytokines. Among these constitutive cell-autonomous responses, autophagy is prominent and its role in innate immunity has been well characterized. Other stress responses, such as metabolic stress, the ER stress/unfolded protein response, mitochondrial stress, or the DNA damage response, seem to also be involved in innate immunity, although the precise mechanisms by which they regulate the innate immune response are not yet defined. Of importance, these distinct constitutive cell-autonomous responses appear to be interconnected and can also be modulated by microbes and PRRs, which add further complexity to the interplay between innate immune signaling and cell-autonomous responses in the mediation of an efficient innate immune response.
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Affiliation(s)
- Julien Moretti
- Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - J Magarian Blander
- Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA; .,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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58
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Mollereau B, Rzechorzek NM, Roussel BD, Sedru M, Van den Brink DM, Bailly-Maitre B, Palladino F, Medinas DB, Domingos PM, Hunot S, Chandran S, Birman S, Baron T, Vivien D, Duarte CB, Ryoo HD, Steller H, Urano F, Chevet E, Kroemer G, Ciechanover A, Calabrese EJ, Kaufman RJ, Hetz C. Adaptive preconditioning in neurological diseases - therapeutic insights from proteostatic perturbations. Brain Res 2016; 1648:603-616. [PMID: 26923166 PMCID: PMC5010532 DOI: 10.1016/j.brainres.2016.02.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 02/16/2016] [Indexed: 02/06/2023]
Abstract
In neurological disorders, both acute and chronic neural stress can disrupt cellular proteostasis, resulting in the generation of pathological protein. However in most cases, neurons adapt to these proteostatic perturbations by activating a range of cellular protective and repair responses, thus maintaining cell function. These interconnected adaptive mechanisms comprise a 'proteostasis network' and include the unfolded protein response, the ubiquitin proteasome system and autophagy. Interestingly, several recent studies have shown that these adaptive responses can be stimulated by preconditioning treatments, which confer resistance to a subsequent toxic challenge - the phenomenon known as hormesis. In this review we discuss the impact of adaptive stress responses stimulated in diverse human neuropathologies including Parkinson׳s disease, Wolfram syndrome, brain ischemia, and brain cancer. Further, we examine how these responses and the molecular pathways they recruit might be exploited for therapeutic gain. This article is part of a Special Issue entitled SI:ER stress.
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Affiliation(s)
- B Mollereau
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France.
| | - N M Rzechorzek
- Centre for Clinical Brain Sciences, Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom; Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin, Midlothian EH25 9RG, United Kingdom
| | - B D Roussel
- Inserm, UMR-S U919 Serine Proteases and Pathophysiology of the Neurovascular Unit, 14000 Caen, France
| | - M Sedru
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - D M Van den Brink
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - B Bailly-Maitre
- INSERM U1065, C3M, Team 8 (Hepatic Complications in Obesity), Nice, France
| | - F Palladino
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - D B Medinas
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Center for Molecular Studies of the Cell, Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile
| | - P M Domingos
- ITQB-UNL, Av. da Republica, EAN, 2780-157 Oeiras, Portugal
| | - S Hunot
- Inserm, U 1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - S Chandran
- Centre for Clinical Brain Sciences, Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom
| | - S Birman
- Genes Circuits Rhythms and Neuropathology, Brain Plasticity Unit, CNRS UMR 8249, ESPCI ParisTech, PSL Research University, 75005 Paris, France
| | - T Baron
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Neurodegenerative Diseases Unit, 31, avenue Tony Garnier, 69364 Lyon Cedex 07, France
| | - D Vivien
- Inserm, UMR-S U919 Serine Proteases and Pathophysiology of the Neurovascular Unit, 14000 Caen, France
| | - C B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Faculty of Medicine, Rua Larga, and Department of Life Sciences, University of Coimbra, 3004-504 Coimbra, Portugal
| | - H D Ryoo
- Department of Cell Biology, New York University School of Medicine, New York, NY, USA
| | - H Steller
- Howard Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - F Urano
- Washington University School of Medicine, Department of Internal Medicine, St. Louis, MO 63110 USA
| | - E Chevet
- Inserm ERL440 "Oncogenesis, Stress, Signaling", Université de Rennes 1, Rennes, France; Centre de Lutte Contre le Cancer Eugène Marquis, Rennes, France
| | - G Kroemer
- Equipe 11 labellisée par la Ligue contre le Cancer, Centre de Recherche des Cordeliers, Paris, France; Cell Biology and Metabolomics platforms, Gustave Roussy Comprehensive Cancer Center, Villejuif, France; INSERM, U1138, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie, Paris, France; Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France; Karolinska Institute, Department of Women׳s and Children׳s Health, Karolinska University Hospital, Stockholm, Sweden
| | - A Ciechanover
- The Polak Cancer and Vascular Biology Research Center, The Rappaport Faculty of Medicine and Research Institute, Technion-Israel Institute of Technology, Haifa 30196, Israel
| | - E J Calabrese
- Department of Environmental Health Sciences, University of Massachusetts, Morrill I, N344, Amherst, MA 01003, USA
| | - R J Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - C Hetz
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Center for Molecular Studies of the Cell, Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
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59
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Menopause-induced uterine epithelium atrophy results from arachidonic acid/prostaglandin E2 axis inhibition-mediated autophagic cell death. Sci Rep 2016; 6:31408. [PMID: 27506466 PMCID: PMC4979008 DOI: 10.1038/srep31408] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 07/21/2016] [Indexed: 02/05/2023] Open
Abstract
Women experience menopause later in life. Menopause is characterized by dramatically decreased circulating estrogen level secondary to loss of ovarian function and atrophic state of genital organs. However, the molecular mechanisms for this process are not fully understood. In this study, we aimed to investigate the potential molecular mechanisms that underlie menopause-induced uterine endometrial atrophy. Our data showed that autophagy was activated in the uterine epithelial cells of both ovariectomized rats and peri-menopausal females. Endoplasmic reticulum (ER) stress occurred even prior to autophagy induction. Integrated bioinformatics analysis revealed that ER stress induced downstream decreased release of arachidonic acid (AA) and downregulation of AA/prostaglandin E2 (PGE2) axis, which led to Akt/mTOR signaling pathway inactivation. Consequently, autophagosomes were recruited and LC3-dependent autophagy was induced in uterine epithelial cells. Treatment with exogenous E2, PGE2, salubrinal or RNAi-mediated silencing of key autophagy genes could effectively counteract estrogen depletion-induced autophagy. Collectively, autophagy is a critical regulator of the uterine epithelium that accounts for endometrial atrophy after menopause.
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60
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Xue P, Li B, An Y, Sun J, He X, Hou R, Dong G, Fei D, Jin F, Wang Q, Jin Y. Decreased MORF leads to prolonged endoplasmic reticulum stress in periodontitis-associated chronic inflammation. Cell Death Differ 2016; 23:1862-1872. [PMID: 27447113 DOI: 10.1038/cdd.2016.74] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 06/22/2016] [Accepted: 06/24/2016] [Indexed: 02/06/2023] Open
Abstract
The association between inflammation and endoplasmic reticulum (ER) stress has been described in many diseases. However, if and how chronic inflammation governs the unfolded protein response (UPR) and promotes ER homeostasis of chronic inflammatory disease remains elusive. In this study, chronic inflammation resulted in ER stress in mesenchymal stem cells in the setting of periodontitis. Long-term proinflammatory cytokines induced prolonged ER stress and decreased the osteogenic differentiation of periodontal ligament stem cells (PDLSCs). Interestingly, we showed that chronic inflammation decreases the expression of lysine acetyltransferase 6B (KAT6B, also called MORF), a histone acetyltransferase, and causes the upregulation of a key UPR sensor, PERK, which lead to the persistent activation of the UPR in PDLSCs. Furthermore, we found that the activation of UPR mediated by MORF in chronic inflammation contributes to the PERK-related deterioration of the osteogenic differentiation of PDLSCs both in vivo and in vitro. Taken together, our results suggest that chronic inflammation compromises UPR function through MORF-mediated-PERK transcription, which is a previously unrecognized mechanism that contributes to impaired ER function, prolonged ER stress and defective osteogenic differentiation of PDLSCs in periodontitis.
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Affiliation(s)
- Peng Xue
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Department of Periodontology, School of Stomatology, The Fourth Military Medical University, Shaanxi Key Laboratory of Stomatology, Xi'an, Shaanxi 710032, China.,State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Bei Li
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Ying An
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Department of Periodontology, School of Stomatology, The Fourth Military Medical University, Shaanxi Key Laboratory of Stomatology, Xi'an, Shaanxi 710032, China.,State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Jin Sun
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China.,Department of Stomatology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510140, China
| | - Xiaoning He
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Rui Hou
- State Key Laboratory of Military Stomatology, Department of Oral and Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Guangying Dong
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Department of Periodontology, School of Stomatology, The Fourth Military Medical University, Shaanxi Key Laboratory of Stomatology, Xi'an, Shaanxi 710032, China
| | - Dongdong Fei
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Department of Periodontology, School of Stomatology, The Fourth Military Medical University, Shaanxi Key Laboratory of Stomatology, Xi'an, Shaanxi 710032, China.,State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Fang Jin
- State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
| | - Qintao Wang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Department of Periodontology, School of Stomatology, The Fourth Military Medical University, Shaanxi Key Laboratory of Stomatology, Xi'an, Shaanxi 710032, China
| | - Yan Jin
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Disease, Center for Tissue Engineering, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, China
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Menon R, Bonney EA, Condon J, Mesiano S, Taylor RN. Novel concepts on pregnancy clocks and alarms: redundancy and synergy in human parturition. Hum Reprod Update 2016; 22:535-60. [PMID: 27363410 DOI: 10.1093/humupd/dmw022] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 05/16/2016] [Indexed: 12/19/2022] Open
Abstract
The signals and mechanisms that synchronize the timing of human parturition remain a mystery and a better understanding of these processes is essential to avert adverse pregnancy outcomes. Although our insights into human labor initiation have been informed by studies in animal models, the timing of parturition relative to fetal maturation varies among viviparous species, indicative of phylogenetically different clocks and alarms; but what is clear is that important common pathways must converge to control the birth process. For example, in all species, parturition involves the transition of the myometrium from a relaxed to a highly excitable state, where the muscle rhythmically and forcefully contracts, softening the cervical extracellular matrix to allow distensibility and dilatation and thus a shearing of the fetal membranes to facilitate their rupture. We review a number of theories promulgated to explain how a variety of different timing mechanisms, including fetal membrane cell senescence, circadian endocrine clocks, and inflammatory and mechanical factors, are coordinated as initiators and effectors of parturition. Many of these factors have been independently described with a focus on specific tissue compartments.In this review, we put forth the core hypothesis that fetal membrane (amnion and chorion) senescence is the initiator of a coordinated, redundant signal cascade leading to parturition. Whether modified by oxidative stress or other factors, this process constitutes a counting device, i.e. a clock, that measures maturation of the fetal organ systems and the production of hormones and other soluble mediators (including alarmins) and that promotes inflammation and orchestrates an immune cascade to propagate signals across different uterine compartments. This mechanism in turn sensitizes decidual responsiveness and eventually promotes functional progesterone withdrawal in the myometrium, leading to increased myometrial cell contraction and the triggering of parturition. Linkage of these processes allows convergence and integration of the gestational clocks and alarms, prompting a timely and safe birth. In summary, we provide a comprehensive synthesis of the mediators that contribute to the timing of human labor. Integrating these concepts will provide a better understanding of human parturition and ultimately improve pregnancy outcomes.
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Affiliation(s)
- Ramkumar Menon
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine and Perinatal Research, The University of Texas Medical Branch at Galveston, 301 University Blvd., MRB, Room 11.138, Galveston, TX 77555-1062, USA
| | - Elizabeth A Bonney
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Vermont College of Medicine, 792 College Parkway, Fanny Allen Campus, Suite 101, Colchester, Burlington, VT 05446, USA
| | - Jennifer Condon
- Department of Obstetrics and Gynecology, Wayne State University, Perinatal Research Branch, NICHD, Detroit, MI 48201, USA
| | - Sam Mesiano
- Department of Reproductive Biology and Obstetrics and Gynecology, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH 44106, USA
| | - Robert N Taylor
- Department of Obstetrics and Gynecology, Medical Center Boulevard, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
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Grootjans J, Kaser A, Kaufman RJ, Blumberg RS. The unfolded protein response in immunity and inflammation. Nat Rev Immunol 2016; 16:469-84. [PMID: 27346803 DOI: 10.1038/nri.2016.62] [Citation(s) in RCA: 508] [Impact Index Per Article: 63.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The unfolded protein response (UPR) is a highly conserved pathway that allows the cell to manage endoplasmic reticulum (ER) stress that is imposed by the secretory demands associated with environmental forces. In this role, the UPR has increasingly been shown to have crucial functions in immunity and inflammation. In this Review, we discuss the importance of the UPR in the development, differentiation, function and survival of immune cells in meeting the needs of an immune response. In addition, we review current insights into how the UPR is involved in complex chronic inflammatory diseases and, through its role in immune regulation, antitumour responses.
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Affiliation(s)
- Joep Grootjans
- Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts 02115, USA
| | - Arthur Kaser
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Randal J Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, USA
| | - Richard S Blumberg
- Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts 02115, USA
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Wang Y, Gong J, Zeng H, Liu R, Jin B, Chen L, Wang Q. Lipopolysaccharide Activates the Unfolded Protein Response in Human Periodontal Ligament Fibroblasts. J Periodontol 2016; 87:e75-81. [DOI: 10.1902/jop.2015.150413] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Martins AS, Alves I, Helguero L, Domingues MR, Neves BM. The Unfolded Protein Response in Homeostasis and Modulation of Mammalian Immune Cells. Int Rev Immunol 2016; 35:457-476. [PMID: 27119724 DOI: 10.3109/08830185.2015.1110151] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The endoplasmic reticulum (ER) plays important roles in eukaryotic protein folding and lipid biosynthesis. Several exogenous and endogenous cellular sources of stress can perturb ER homeostasis leading to the accumulation of unfolded proteins in the lumen. Unfolded protein accumulation triggers a signal-transduction cascade known as the unfolded protein response (UPR), an adaptive mechanism which aims to protect cells from protein aggregates and to restore ER functions. Further to this protective mechanism, in immune cells, UPR molecular effectors have been shown to participate in a wide range of biological processes such as cell differentiation, survival and immunoglobulin and cytokine production. Recent findings also highlight the involvement of the UPR machinery in the maturational program and antigen presentation capacities of dendritic cells. UPR is therefore a key element in immune system homeostasis with direct implications on both adaptive and innate immune responses. The present review summarizes the knowledge on the emerging roles of UPR signaling cascades in mammalian immune cells as well as the consequences of their dysregulation in relation to the pathogenesis of several diseases.
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Affiliation(s)
- Ana Sofia Martins
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Inês Alves
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Luisa Helguero
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal.,b Institute for Research in Biomedicine - iBiMED, Health Sciences Program, Universidade de Aveiro , Portugal
| | - Maria Rosário Domingues
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Bruno Miguel Neves
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal.,c Faculty of Pharmacy and Centre for Neuroscience and Cell Biology, University of Coimbra , Coimbra , Portugal
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Webster SJ, Ellis L, O'Brien LM, Tyrrell B, Fitzmaurice TJ, Elder MJ, Clare S, Chee R, Gaston JSH, Goodall JC. IRE1α mediates PKR activation in response to Chlamydia trachomatis infection. Microbes Infect 2016; 18:472-83. [PMID: 27021640 PMCID: PMC4936793 DOI: 10.1016/j.micinf.2016.03.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Revised: 02/09/2016] [Accepted: 03/18/2016] [Indexed: 12/20/2022]
Abstract
Protein kinase RNA activated (PKR) is a crucial mediator of anti-viral responses but is reported to be activated by multiple non-viral stimuli. However, mechanisms underlying PKR activation, particularly in response to bacterial infection, remain poorly understood. We have investigated mechanisms of PKR activation in human primary monocyte-derived dendritic cells in response to infection by Chlamydia trachomatis. Infection resulted in potent activation of PKR that was dependent on TLR4 and MyD88 signalling. NADPH oxidase was dispensable for activation of PKR as cells from chronic granulomatous disease (CGD) patients, or mice that lack NADPH oxidase activity, had equivalent or elevated PKR activation. Significantly, stimulation of cells with endoplasmic reticulum (ER) stress-inducing agents resulted in potent activation of PKR that was blocked by an inhibitor of IRE1α RNAse activity. Crucially, infection resulted in robust IRE1α RNAse activity that was dependent on TLR4 signalling and inhibition of IRE1α RNAse activity prevented PKR activation. Finally, we demonstrate that TLR4/IRE1α mediated PKR activation is required for the enhancement of interferon-β production following C. trachomatis infection. Thus, we provide evidence of a novel mechanism of PKR activation requiring ER stress signalling that occurs as a consequence of TLR4 stimulation during bacterial infection and contributes to inflammatory responses.
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Affiliation(s)
- Steve J Webster
- Rheumatology Research Group, Department of Medicine, University of Cambridge, UK
| | - Lou Ellis
- Rheumatology Research Group, Department of Medicine, University of Cambridge, UK
| | - Louise M O'Brien
- Rheumatology Research Group, Department of Medicine, University of Cambridge, UK
| | - Beatrice Tyrrell
- Rheumatology Research Group, Department of Medicine, University of Cambridge, UK
| | | | - Matthew J Elder
- Rheumatology Research Group, Department of Medicine, University of Cambridge, UK
| | - Simon Clare
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK
| | - Ronnie Chee
- Department of Immunology, Royal Free Hospital, London, UK
| | - J S Hill Gaston
- Rheumatology Research Group, Department of Medicine, University of Cambridge, UK
| | - Jane C Goodall
- Rheumatology Research Group, Department of Medicine, University of Cambridge, UK.
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Snodgrass RG, Huang S, Namgaladze D, Jandali O, Shao T, Sama S, Brüne B, Hwang DH. Docosahexaenoic acid and palmitic acid reciprocally modulate monocyte activation in part through endoplasmic reticulum stress. J Nutr Biochem 2016; 32:39-45. [PMID: 27142735 DOI: 10.1016/j.jnutbio.2016.01.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Revised: 01/05/2016] [Accepted: 01/23/2016] [Indexed: 12/22/2022]
Abstract
Palmitic acid (C16:0) and TLR2 ligand induce, but docosahexaenoic acid (DHA) inhibits monocyte activation. C16:0 and TLR2 or TLR4 ligand induce certain ER stress markers; thus, we determined whether ER stress induced by these agonists is sufficient to induce monocyte activation, and whether the ER stress is inhibited by DHA which is known to inhibit C16:0- or ligand-induced TLR activation. Monocyte activation and ER stress were assessed by TLR/inflammasome-induced IL-1β production, and phosphorylation of IRE-1 and eIF2 and expression of CHOP, respectively in THP-1 cells. TLR2 ligand Pam3CSK4 induced phosphorylation of eIF2, but not phosphorylation of IRE-1 and CHOP expression. LPS also induced phosphorylation of both IRE-1 and eIF2 but not CHOP expression suggesting that TLR2 or TLR4 ligand, or C16:0 induces different ER stress responses. C16:0-, Pam3CSK4-, or LPS-induced IL-1β production was inhibited by 4-phenylbutyric acid, an inhibitor of ER stress suggesting that IL-1β production induced by these agonists is partly mediated through ER stress. Among two ER stress-inducing molecules, thapsigargin but not tunicamycin led to the expression of pro-IL-1β and secretion of IL-1β. Thus, not all types of ER stress are sufficient to induce inflammasome-mediated IL-1β secretion in monocytes. Although both C16:0 and thapsigargin-induced IL-1β secretion was inhibited by DHA, only C16:0-mediated ER stress was responsive to DHA. These findings suggest that the anti-inflammatory effects of DHA are at least in part mediated through modulating ER homeostasis and that the propensity of ER stress can be differentially modulated by the types of dietary fat we consume.
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Affiliation(s)
- Ryan G Snodgrass
- U.S. Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616; Institute of Biochemistry I, Goethe-University Frankfurt, Frankfurt, Germany
| | - Shurong Huang
- U.S. Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616
| | - Dmitry Namgaladze
- Institute of Biochemistry I, Goethe-University Frankfurt, Frankfurt, Germany
| | - Ola Jandali
- U.S. Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616
| | - Tiffany Shao
- U.S. Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616
| | - Spandana Sama
- U.S. Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616
| | - Bernhard Brüne
- Institute of Biochemistry I, Goethe-University Frankfurt, Frankfurt, Germany
| | - Daniel H Hwang
- U.S. Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616.
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Ishizawa J, Kojima K, Chachad D, Ruvolo P, Ruvolo V, Jacamo RO, Borthakur G, Mu H, Zeng Z, Tabe Y, Allen JE, Wang Z, Ma W, Lee HC, Orlowski R, Sarbassov DD, Lorenzi PL, Huang X, Neelapu SS, McDonnell T, Miranda RN, Wang M, Kantarjian H, Konopleva M, Davis RE, Andreeff M. ATF4 induction through an atypical integrated stress response to ONC201 triggers p53-independent apoptosis in hematological malignancies. Sci Signal 2016; 9:ra17. [PMID: 26884599 DOI: 10.1126/scisignal.aac4380] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The clinical challenge posed by p53 abnormalities in hematological malignancies requires therapeutic strategies other than standard genotoxic chemotherapies. ONC201 is a first-in-class small molecule that activates p53-independent apoptosis, has a benign safety profile, and is in early clinical trials. We found that ONC201 caused p53-independent apoptosis and cell cycle arrest in cell lines and in mantle cell lymphoma (MCL) and acute myeloid leukemia (AML) samples from patients; these included samples from patients with genetic abnormalities associated with poor prognosis or cells that had developed resistance to the nongenotoxic agents ibrutinib and bortezomib. Moreover, ONC201 caused apoptosis in stem and progenitor AML cells and abrogated the engraftment of leukemic stem cells in mice while sparing normal bone marrow cells. ONC201 caused changes in gene expression similar to those caused by the unfolded protein response (UPR) and integrated stress responses (ISRs), which increase the translation of the transcription factor ATF4 through an increase in the phosphorylation of the translation initiation factor eIF2α. However, unlike the UPR and ISR, the increase in ATF4 abundance in ONC201-treated hematopoietic cells promoted apoptosis and did not depend on increased phosphorylation of eIF2α. ONC201 also inhibited mammalian target of rapamycin complex 1 (mTORC1) signaling, likely through ATF4-mediated induction of the mTORC1 inhibitor DDIT4. Overexpression of BCL-2 protected against ONC201-induced apoptosis, and the combination of ONC201 and the BCL-2 antagonist ABT-199 synergistically increased apoptosis. Thus, our results suggest that by inducing an atypical ISR and p53-independent apoptosis, ONC201 has clinical potential in hematological malignancies.
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Affiliation(s)
- Jo Ishizawa
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kensuke Kojima
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA. Division of Hematology, Respiratory Medicine and Oncology, Department of Medicine, Saga University, Saga 840-8502, Japan
| | - Dhruv Chachad
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Peter Ruvolo
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Vivian Ruvolo
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Rodrigo O Jacamo
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Gautam Borthakur
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hong Mu
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Zhihong Zeng
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Yoko Tabe
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA. Department of Clinical Laboratory Medicine, Juntendo University School of Medicine, Tokyo 113-8431, Japan
| | | | - Zhiqiang Wang
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Wencai Ma
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hans C Lee
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Robert Orlowski
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Dos D Sarbassov
- Department of Molecular and Cellular Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Philip L Lorenzi
- Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Xuelin Huang
- Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Sattva S Neelapu
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Timothy McDonnell
- Department of Hematopathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Roberto N Miranda
- Department of Hematopathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Michael Wang
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hagop Kantarjian
- Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Marina Konopleva
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - R Eric Davis
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Michael Andreeff
- Section of Molecular Hematology and Therapy, Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
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Liao K, Guo M, Niu F, Yang L, Callen SE, Buch S. Cocaine-mediated induction of microglial activation involves the ER stress-TLR2 axis. J Neuroinflammation 2016; 13:33. [PMID: 26860188 PMCID: PMC4748483 DOI: 10.1186/s12974-016-0501-2] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 02/01/2016] [Indexed: 12/21/2022] Open
Abstract
Background Neuroinflammation associated with advanced human immunodeficiency virus (HIV)-1 infection is often exacerbated by chronic cocaine abuse. Cocaine exposure has been demonstrated to mediate up-regulation of inflammatory mediators in in vitro cultures of microglia. The molecular mechanisms involved in this process, however, remain poorly understood. In this study, we sought to explore the underlying signaling pathways involved in cocaine-mediated activation of microglial cells. Methods BV2 microglial cells were exposed to cocaine and assessed for toll-like receptor (TLR2) expression by quantitative polymerase chain reaction (qPCR), western blot, flow cytometry, and immunofluorescence staining. The mRNA and protein levels of cytokines (TNFα, IL-6, MCP-1) were detected by qPCR and ELISA, respectively; level of reactive oxygen species (ROS) production was examined by the Image-iT LIVE Green ROS detection kit; activation of endoplasmic reticulum (ER)-stress pathways were detected by western blot. Chromatin immunoprecipitation (ChIP) assay was employed to discern the binding of activating transcription factor 4 (ATF4) with the TLR2 promoter. Immunoprecipitation followed by western blotting with tyrosine antibody was used to determine phosphorylation of TLR2. Cocaine-mediated up-regulation of TLR2 expression and microglial activation was validated in cocaine-injected mice. Results Exposure of microglial cells to cocaine resulted in increased expression of TLR2 with a concomitant induction of microglial activation. Furthermore, this effect was mediated by NADPH oxidase-mediated rapid accumulation of ROS with downstream activation of the ER-stress pathways as evidenced by the fact that cocaine exposure led to up-regulation of pPERK/peIF2α/ATF4 and TLR2. The novel role of ATF4 in the regulation of TLR2 expression was confirmed using genetic and pharmacological approaches. Conclusions xThe current study demonstrates that cocaine-mediated activation of microglia involves up-regulation of TLR2 through the ROS-ER stress-ATF4-TLR2 axis. Understanding the mechanism(s) involved in cocaine-mediated up-regulation of ROS-ER stress/TLR2 expression and microglial activation could have implications for the development of potential therapeutic targets aimed at resolving neuroinflammation in cocaine abusers. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0501-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ke Liao
- Department of Pharmacology and Experimental Neuroscience, 985880 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| | - Minglei Guo
- Department of Pharmacology and Experimental Neuroscience, 985880 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| | - Fang Niu
- Department of Pharmacology and Experimental Neuroscience, 985880 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| | - Lu Yang
- Department of Pharmacology and Experimental Neuroscience, 985880 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| | - Shannon E Callen
- Department of Pharmacology and Experimental Neuroscience, 985880 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| | - Shilpa Buch
- Department of Pharmacology and Experimental Neuroscience, 985880 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
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An inhibitor of HIV-1 protease modulates constitutive eIF2α dephosphorylation to trigger a specific integrated stress response. Proc Natl Acad Sci U S A 2015; 113:E117-26. [PMID: 26715744 DOI: 10.1073/pnas.1514076113] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Inhibitors of the HIV aspartyl protease [HIV protease inhibitors (HIV-PIs)] are the cornerstone of treatment for HIV. Beyond their well-defined antiretroviral activity, these drugs have additional effects that modulate cell viability and homeostasis. However, little is known about the virus-independent pathways engaged by these molecules. Here we show that the HIV-PI Nelfinavir decreases translation rates and promotes a transcriptional program characteristic of the integrated stress response (ISR). Mice treated with Nelfinavir display hallmarks of this stress response in the liver, including α subunit of translation initiation factor 2 (eIF2α) phosphorylation, activating transcription factor-4 (ATF4) induction, and increased expression of known downstream targets. Mechanistically, Nelfinavir-mediated ISR bypassed direct activation of the eIF2α stress kinases and instead relied on the inhibition of the constitutive eIF2α dephosphorylation and down-regulation of the phophatase cofactor CReP (Constitutive Repressor of eIF2α Phosphorylation; also known as PPP1R15B). These findings demonstrate that the modulation of eIF2α-specific phosphatase cofactor activity can be a rheostat of cellular homeostasis that initiates a functional ISR and suggest that the HIV-PIs could be repositioned as therapeutics in human diseases to modulate translation rates and stress responses.
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Kandel-Kfir M, Almog T, Shaish A, Shlomai G, Anafi L, Avivi C, Barshack I, Grosskopf I, Harats D, Kamari Y. Interleukin-1α deficiency attenuates endoplasmic reticulum stress-induced liver damage and CHOP expression in mice. J Hepatol 2015; 63:926-33. [PMID: 26022690 DOI: 10.1016/j.jhep.2015.05.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 05/01/2015] [Accepted: 05/11/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS ER stress promotes liver fat accumulation and induction of inflammatory cytokines, which contribute to the development of steatohepatitis. Unresolved ER stress upregulates the pro-apoptotic CHOP. IL-1α is localized to the nucleus in apoptotic cells, but is released when these cells become necrotic and induce sterile inflammation. We investigated whether IL-1α is involved in ER stress-induced apoptosis and steatohepatitis. METHODS We employed WT and IL-1α-deficient mice to study the role of IL-1α in ER stress-induced steatohepatitis. RESULTS Liver CHOP mRNA was induced in a time dependent fashion in the atherogenic diet-induced steatohepatitis model, and was twofold lower in IL-1α deficient compared to WT mice. In the ER stress-driven steatohepatitis model, IL-1α deficiency decreased the elevation in serum ALT levels, the number of apoptotic cells (measured as caspase-3-positive hepatocytes), and the expression of IL-1β, IL-6, TNFα, and CHOP, with no effect on the degree of fatty liver formation. IL-1α was upregulated in ER-stressed-macrophages and the protein was localized to the nucleus. IL-1β mRNA and CHOP mRNA and protein levels were lower in ER-stressed-macrophages from IL-1α deficient compared to WT mice. ER stress induced the expression of IL-1α and IL-1β also in mouse primary hepatocytes. Recombinant IL-1α treatment in hepatocytes did not affect CHOP expression but upregulated both IL-1α and IL-1β mRNA levels. CONCLUSION We show that IL-1α is upregulated in response to ER stress and IL-1α deficiency reduces ER stress-induced CHOP expression, apoptosis and steatohepatitis. As a dual function cytokine, IL-1α may contribute to the induction of CHOP intracellularly, while IL-1α released from necrotic cells accelerates steatohepatitis via induction of inflammatory cytokines by neighboring cells.
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Affiliation(s)
- Michal Kandel-Kfir
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Tal Almog
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Aviv Shaish
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Gadi Shlomai
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Liat Anafi
- The Pathology Department, Sheba Medical Center, Tel Hashomer, Israel
| | - Camila Avivi
- The Pathology Department, Sheba Medical Center, Tel Hashomer, Israel
| | - Iris Barshack
- The Pathology Department, Sheba Medical Center, Tel Hashomer, Israel; Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - Itamar Grosskopf
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Dror Harats
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel Hashomer, Israel; Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - Yehuda Kamari
- The Bert W. Strassburger Lipid Center, Sheba Medical Center, Tel Hashomer, Israel; Sackler Faculty of Medicine, Tel-Aviv University, Israel.
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Abstract
Stress induced by accumulation of misfolded proteins in the endoplasmic reticulum is observed in many physiological and pathological conditions. To cope with endoplasmic reticulum stress, cells activate the unfolded protein response, a dynamic signalling network that orchestrates the recovery of homeostasis or triggers apoptosis, depending on the level of damage. Here we provide an overview of recent insights into the mechanisms that cells employ to maintain proteostasis and how the unfolded protein response determines cell fate under endoplasmic reticulum stress.
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73
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Dufey E, Urra H, Hetz C. ER proteostasis addiction in cancer biology: Novel concepts. Semin Cancer Biol 2015; 33:40-7. [PMID: 25931388 DOI: 10.1016/j.semcancer.2015.04.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 04/15/2015] [Accepted: 04/20/2015] [Indexed: 01/22/2023]
Abstract
Endoplasmic reticulum (ER) stress is generated by various physiological and pathological conditions that induce an accumulation of misfolded proteins in its lumen. ER stress activates the unfolded protein response (UPR), an adaptive reaction to cope with protein misfolding to and restore proteostasis. However, chronic ER stress results in apoptosis. In solid tumors, the UPR mediates adaptation to various environmental stressors, including hypoxia, low in pH and low nutrients availability, driving positive selection. Recent findings support the concept that UPR signaling also contributes to other relevant cancer-related event that may not be related to ER stress, including angiogenesis, genomic instability, metastasis and immunomodulation. In this article, we overview novel discoveries highlighting the impact of the UPR to different aspects of cancer biology beyond its known role as a survival factor to the hypoxic environment observed in solid tumors.
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Affiliation(s)
- Estefanie Dufey
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Center for Molecular Studies of the Cell, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Hery Urra
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Center for Molecular Studies of the Cell, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Center for Molecular Studies of the Cell, Faculty of Medicine, University of Chile, Santiago, Chile; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA.
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74
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Cunard R. Endoplasmic Reticulum Stress in the Diabetic Kidney, the Good, the Bad and the Ugly. J Clin Med 2015; 4:715-40. [PMID: 26239352 PMCID: PMC4470163 DOI: 10.3390/jcm4040715] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 03/31/2015] [Indexed: 02/06/2023] Open
Abstract
Diabetic kidney disease is the leading worldwide cause of end stage kidney disease and a growing public health challenge. The diabetic kidney is exposed to many environmental stressors and each cell type has developed intricate signaling systems designed to restore optimal cellular function. The unfolded protein response (UPR) is a homeostatic pathway that regulates endoplasmic reticulum (ER) membrane structure and secretory function. Studies suggest that the UPR is activated in the diabetic kidney to restore normal ER function and viability. However, when the cell is continuously stressed in an environment that lies outside of its normal physiological range, then the UPR is known as the ER stress response. The UPR reduces protein synthesis, augments the ER folding capacity and downregulates mRNA expression of genes by multiple pathways. Aberrant activation of ER stress can also induce inflammation and cellular apoptosis, and modify signaling of protective processes such as autophagy and mTORC activation. The following review will discuss our current understanding of ER stress in the diabetic kidney and explore novel means of modulating ER stress and its interacting signaling cascades with the overall goal of identifying therapeutic strategies that will improve outcomes in diabetic nephropathy.
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Affiliation(s)
- Robyn Cunard
- Research Service and Division of Nephrology-Hypertension, Veterans Affairs San Diego Healthcare System, Veterans Medical Research Foundation, San Diego, CA 92161, USA.
- Department of Medicine, University of California San Diego, La Jolla, CA 92093, USA.
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75
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Sidrauski C, McGeachy AM, Ingolia NT, Walter P. The small molecule ISRIB reverses the effects of eIF2α phosphorylation on translation and stress granule assembly. eLife 2015; 4:e05033. [PMID: 25719440 PMCID: PMC4341466 DOI: 10.7554/elife.05033] [Citation(s) in RCA: 405] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 02/04/2015] [Indexed: 12/16/2022] Open
Abstract
Previously, we identified ISRIB as a potent inhibitor of the integrated stress response (ISR) and showed that ISRIB makes cells resistant to the effects of eIF2α phosphorylation and enhances long-term memory in rodents (Sidrauski et al., 2013). Here, we show by genome-wide in vivo ribosome profiling that translation of a restricted subset of mRNAs is induced upon ISR activation. ISRIB substantially reversed the translational effects elicited by phosphorylation of eIF2α and induced no major changes in translation or mRNA levels in unstressed cells. eIF2α phosphorylation-induced stress granule (SG) formation was blocked by ISRIB. Strikingly, ISRIB addition to stressed cells with pre-formed SGs induced their rapid disassembly, liberating mRNAs into the actively translating pool. Restoration of mRNA translation and modulation of SG dynamics may be an effective treatment of neurodegenerative diseases characterized by eIF2α phosphorylation, SG formation, and cognitive loss.
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Affiliation(s)
- Carmela Sidrauski
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francis, San Francisco, United States
| | - Anna M McGeachy
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Nicholas T Ingolia
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Peter Walter
- Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francis, San Francisco, United States
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76
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Jacobs J, Braun J. The Mucosal Microbiome. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00005-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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77
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Argüello RJ, Rodriguez Rodrigues C, Gatti E, Pierre P. Protein synthesis regulation, a pillar of strength for innate immunity? Curr Opin Immunol 2014; 32:28-35. [PMID: 25553394 DOI: 10.1016/j.coi.2014.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/04/2014] [Accepted: 12/10/2014] [Indexed: 12/31/2022]
Abstract
Recognition of pathogen derived molecules by Pattern Recognition Receptors (PRR) induces the production of cytokines (i.e. type I interferons) that stimulate the surrounding cells to transcribe and translate hundreds of genes, in order to prevent further infection and organize the immune response. Here, we report on the rising matter that metabolism sensing and gene expression control at the level of mRNA translation, allow swift responses that mobilize host defenses and coordinate innate responses to infection.
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Affiliation(s)
- Rafael J Argüello
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Christian Rodriguez Rodrigues
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
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78
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Emerging functions of the unfolded protein response in immunity. Nat Immunol 2014; 15:910-9. [PMID: 25232821 DOI: 10.1038/ni.2991] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 08/18/2014] [Indexed: 12/14/2022]
Abstract
The unfolded protein response (UPR) has traditionally been viewed as an adaptive response triggered by the accumulation of unfolded proteins in the endoplasmic reticulum (ER) and aimed at restoring ER function. The UPR can also be an anticipatory response that is activated well before the disruption of protein homeostasis. UPR signaling intersects at many levels with the innate and adaptive immune responses. In some types of cells of the immune system, such as dendritic cells (DCs) and B cells, particular sensors that detect the UPR seem to be constitutively active in the absence of induction of the traditional UPR gene program and are necessary for antigen presentation and immunoglobulin synthesis. The UPR also influences signaling via Toll-like receptors (TLRs) and activation of the transcription factor NF-κB, and some pathogens subvert the UPR. This Review summarizes these emerging noncanonical functions of the UPR in immunity.
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79
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Tsujii S, Ishisaka M, Shimazawa M, Hashizume T, Hara H. Zonisamide suppresses endoplasmic reticulum stress-induced neuronal cell damage in vitro and in vivo. Eur J Pharmacol 2014; 746:301-7. [PMID: 25261037 DOI: 10.1016/j.ejphar.2014.09.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/16/2014] [Accepted: 09/16/2014] [Indexed: 11/15/2022]
Abstract
Zonisamide has been reported to have protective effects on epilepsy and Parkinson׳s disease and to work via various mechanisms of action, such as inhibition of monoamine oxidase-B and enhancement of tyrosine hydroxylase. Recently, it has been suggested that zonisamide itself shows neuroprotective actions. Therefore, in the present study we investigated the neuroprotective effects of zonisamide against endoplasmic reticulum (ER) stress. We used human neuroblastoma (SH-SY5Y) cells and investigated the protective effects of zonisamide against tunicamycin- and thapsigargin-induced neuronal cell death. In addition, we investigated the effect of zonisamide against 1-methyl-4-phenylpyridinium (MPP⁺)-induced cell death and the mechanism of protection against ER stress. In vivo, we investigated the effect of zonisamide (20 mg/kg, p.o.) in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mouse model of Parkinson׳s disease. Zonisamide not only suppressed MPP⁺-induced cell death, but also inhibited ER stress-induced cell death and suppressed the expression of ER stress-related factors such as C/EBO homologous protein (CHOP) in vivo. Furthermore, zonisamide inhibited the activation of caspase-3 in vitro. These results suggest that zonisamide affected ER stress via caspase-3. We think that ER stress, particularly the mechanism via caspase-3, is involved in part of the neuroprotective effect of zonisamide against the experimental models of Parkinson׳s disease.
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Affiliation(s)
- Saori Tsujii
- Department of Biofunctional Evaluation, Molecular Pharmacology, Gifu Pharmaceutical University, Japan
| | - Mitsue Ishisaka
- Department of Biofunctional Evaluation, Molecular Pharmacology, Gifu Pharmaceutical University, Japan
| | - Masamitsu Shimazawa
- Department of Biofunctional Evaluation, Molecular Pharmacology, Gifu Pharmaceutical University, Japan
| | - Takanori Hashizume
- Laboratory of Drug Metabolism & Pharmacokinetics, Faculty of Pharmacy, Osaka Ohtani University, Japan
| | - Hideaki Hara
- Department of Biofunctional Evaluation, Molecular Pharmacology, Gifu Pharmaceutical University, Japan.
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80
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Manié SN, Lebeau J, Chevet E. Cellular mechanisms of endoplasmic reticulum stress signaling in health and disease. 3. Orchestrating the unfolded protein response in oncogenesis: an update. Am J Physiol Cell Physiol 2014; 307:C901-7. [PMID: 25186011 DOI: 10.1152/ajpcell.00292.2014] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The endoplasmic reticulum (ER)-induced unfolded protein response (UPR) is an adaptive mechanism that is activated upon accumulation of misfolded proteins in the ER and aims at restoring ER homeostasis. In the past 10 years, the UPR has emerged as an important actor in the different phases of tumor growth. The UPR is transduced by three major ER resident stress sensors, which are protein kinase RNA-like ER kinase (PERK), activating transcription factor 6 (ATF6), and inositol-requiring enzyme-1 (IRE1). The signaling pathways elicited by those stress sensors have connections with metabolic pathways and with other plasma membrane receptor signaling networks. As such, the ER has an essential position as a signal integrator in the cell and is instrumental in the different phases of tumor progression. Herein, we describe and discuss the characteristics of an integrated signaling network that might condition the UPR biological outputs in a tissue- or stress-dependent manner. We discuss these issues in the context of the pathophysiological roles of UPR signaling in cancers.
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Affiliation(s)
- Serge N Manié
- University of Lyon, Lyon, France, and UMR CNRS 5286 - INSERM 1052 - University of Lyon, Cancer Research Center of Lyon, Team ER Stress and Tumorigenesis, Lyon, France;
| | - Justine Lebeau
- University of Lyon, Lyon, France, and UMR CNRS 5286 - INSERM 1052 - University of Lyon, Cancer Research Center of Lyon, Team ER Stress and Tumorigenesis, Lyon, France
| | - Eric Chevet
- Inserm U1053, Team Endoplasmic Reticulum Stress and Cancer, Université de Bordeaux, Bordeaux, France; and Centre Régional de Lutte Contre le Cancer Eugène Marquis, Rennes, France
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81
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Wang M, Kaufman RJ. The impact of the endoplasmic reticulum protein-folding environment on cancer development. Nat Rev Cancer 2014; 14:581-97. [PMID: 25145482 DOI: 10.1038/nrc3800] [Citation(s) in RCA: 776] [Impact Index Per Article: 77.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The endoplasmic reticulum (ER) is an essential organelle in eukaryotic cells for the storage and regulated release of calcium and as the entrance to the secretory pathway. Protein misfolding in the ER causes accumulation of misfolded proteins (ER stress) and activation of the unfolded protein response (UPR), which has evolved to maintain a productive ER protein-folding environment. Both ER stress and UPR activation are documented in many different human cancers. In this Review, we summarize the impact of ER stress and UPR activation on every aspect of cancer and discuss outstanding questions for which answers will pave the way for therapeutics.
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Affiliation(s)
- Miao Wang
- Degenerative Diseases Program, Center for Cancer Research, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd, La Jolla, California 92037, USA
| | - Randal J Kaufman
- Degenerative Diseases Program, Center for Cancer Research, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd, La Jolla, California 92037, USA
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82
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Mardones P, Martínez G, Hetz C. Control of systemic proteostasis by the nervous system. Trends Cell Biol 2014; 25:1-10. [PMID: 25174273 DOI: 10.1016/j.tcb.2014.08.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 08/01/2014] [Accepted: 08/04/2014] [Indexed: 10/24/2022]
Abstract
Maintenance of organismal homeostasis depends on the integration of intracellular and external signals, involving the ability to detect molecular perturbations. An explosion of studies in model organisms indicates the occurrence of dynamic communication between alarm pathways engaged by protein-folding stress in neurons that activate adaptive programs in peripheral organs to control cellular proteostasis. Here we review emerging concepts that highlight the contribution of the proteostasis network to the regulation of several aspects of animal physiology through central integration of signals spanning multiple tissues and organs. These recent findings uncover a new layer of functional interrelation between cells that handle and orchestrate the global maintenance of the proteome at the organismal level in a cell-nonautonomous manner.
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Affiliation(s)
- Pablo Mardones
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Center for Molecular Studies of the Cell, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Gabriela Martínez
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Center for Molecular Studies of the Cell, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Program of Cellular and Molecular Biology, Center for Molecular Studies of the Cell, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Neurounion Biomedical Foundation, CENPAR, Santiago, Chile; Department of Immunology and Infectious diseases, Harvard School of Public Health, Boston, MA, USA.
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83
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Häcker G. ER-stress and apoptosis: molecular mechanisms and potential relevance in infection. Microbes Infect 2014; 16:805-10. [PMID: 25172397 DOI: 10.1016/j.micinf.2014.08.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 08/18/2014] [Accepted: 08/19/2014] [Indexed: 02/07/2023]
Abstract
During ER-stress, one of the responses a cell can choose is apoptosis. Apoptosis generally is a cell's preferred response when other control mechanisms are overwhelmed. We now have a reasonably clear molecular picture what is happening once the apoptotic apparatus has been started. Unclear however are the majority of the upstream pathways that connect other signalling to apoptosis. During ER-stress, confirmed apoptosis-regulating targets are pro- and anti-apoptotic proteins of the Bcl-2-family, whose concerted action induces apoptosis. I will here discuss how mitochondrial apoptosis is triggered, how this is linked to the ER-stress response and in what way this may be relevant during microbial infections.
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Affiliation(s)
- Georg Häcker
- Institute for Medical Microbiology and Hygiene, University Medical Centre Freiburg, Hermann Herder-Str. 11, D-79104 Freiburg, Germany.
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84
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van 't Wout EFA, Hiemstra PS, Marciniak SJ. The integrated stress response in lung disease. Am J Respir Cell Mol Biol 2014; 50:1005-9. [PMID: 24605820 DOI: 10.1165/rcmb.2014-0019tr] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lungs are repeatedly exposed to inhaled toxic insults, such as smoke, diesel exhaust, and microbes, which elicit cellular stress responses. The phosphorylation of eukaryotic translation initiation factor 2α by one of four stress-sensing kinases triggers a pathway called the integrated stress response that helps protect cellular reserves of nutrients and prevents the accumulation of toxic proteins. In this review, we discuss how activation of the integrated stress response has been shown to play an important role in pulmonary pathology, and how its study may help in the development of novel therapies for diverse conditions, from hypoxia to cancer.
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Affiliation(s)
- Emily F A van 't Wout
- 1 Department of Pulmonology, Leiden University Medical Centre, Leiden, the Netherlands; and
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85
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Carpenter S, Ricci EP, Mercier BC, Moore MJ, Fitzgerald KA. Post-transcriptional regulation of gene expression in innate immunity. Nat Rev Immunol 2014; 14:361-76. [PMID: 24854588 DOI: 10.1038/nri3682] [Citation(s) in RCA: 275] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Innate immune responses combat infectious microorganisms by inducing inflammatory responses, antimicrobial pathways and adaptive immunity. Multiple genes within each of these functional categories are coordinately and temporally regulated in response to distinct external stimuli. The substantial potential of these responses to drive pathological inflammation and tissue damage highlights the need for rigorous control of these responses. Although transcriptional control of inflammatory gene expression has been studied extensively, the importance of post-transcriptional regulation of these processes is less well defined. In this Review, we discuss the regulatory mechanisms that occur at the level of mRNA splicing, mRNA polyadenylation, mRNA stability and protein translation, and that have instrumental roles in controlling both the magnitude and duration of the inflammatory response.
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Affiliation(s)
- Susan Carpenter
- 1] Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA. [2]
| | - Emiliano P Ricci
- 1] Howard Hughes Medical Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA. [2]
| | - Blandine C Mercier
- 1] Howard Hughes Medical Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA. [2]
| | - Melissa J Moore
- Howard Hughes Medical Institute, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Katherine A Fitzgerald
- 1] Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA. [2] Centre of Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7491 Trondheim, Norway
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86
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Guo B, Li Z. Endoplasmic reticulum stress in hepatic steatosis and inflammatory bowel diseases. Front Genet 2014; 5:242. [PMID: 25120559 PMCID: PMC4110625 DOI: 10.3389/fgene.2014.00242] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/07/2014] [Indexed: 12/17/2022] Open
Abstract
As an adaptive response to the overloading with misfolded proteins in the endoplasmic reticulum (ER), ER stress plays critical roles in maintaining protein homeostasis in the secretory pathway to avoid damage to the host. Such a conserved mechanism is accomplished through three well-orchestrated pathways known collectively as unfolded protein response (UPR). Persistent and pathological ER stress has been implicated in a variety of diseases in metabolic, inflammatory, and malignant conditions. Furthermore, ER stress is directly linked with inflammation through UPR pathways, which modulate transcriptional programs to induce the expression of inflammatory genes. Importantly, the inflammation induced by ER stress is directly responsible for the pathogenesis of metabolic and inflammatory diseases. In this review, we will discuss the potential signaling pathways connecting ER stress with inflammation. We will also depict the interplay between ER stress and inflammation in the pathogenesis of hepatic steatosis, inflammatory bowel diseases and colitis-associated colon cancer.
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Affiliation(s)
- Beichu Guo
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SCUSA
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SCUSA
| | - Zihai Li
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SCUSA
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SCUSA
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87
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25-Hydroxycholesterol acts as an amplifier of inflammatory signaling. Proc Natl Acad Sci U S A 2014; 111:10666-71. [PMID: 24994901 DOI: 10.1073/pnas.1404271111] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Cross-talk between sterol regulatory pathways and inflammatory pathways has been demonstrated to significantly impact the development of both atherosclerosis and infectious disease. The oxysterol 25-hydroxycholesterol (25HC) plays multiple roles in lipid biosynthesis and immunity. We recently used a systems biology approach to identify 25HC as an innate immune mediator that had a predicted role in atherosclerosis and we demonstrated a role for 25HC in foam cell formation. Here, we show that this mediator also has several complex roles in the antiviral response. The host response to viruses involves gene regulatory circuits with multiple feedback loops and we show here that 25HC acts as an amplifier of inflammatory signaling in macrophages. We determined that 25HC amplifies inflammatory signaling, at least in part, by mediating the recruitment of the AP-1 components FBJ osteosarcoma oncogene (FOS) and jun proto-oncogene (JUN) to the promoters of a subset of Toll-like receptor-responsive genes. Consistent with previous reports, we found that 25HC inhibits in vitro infection of airway epithelial cells by influenza. Surprisingly, we found that deletion of Ch25h, the gene encoding the enzyme responsible for 25HC production, is protective in a mouse model of influenza infection as a result of decreased inflammatory-induced pathology. Thus, our study demonstrates, for the first time to our knowledge, that in addition to its direct antiviral role, 25HC also regulates transcriptional responses and acts as an amplifier of inflammation via AP-1 and that the resulting alteration in inflammatory response leads to increased tissue damage in mice following infection with influenza.
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88
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Rodríguez M, Domingo E, Alonso S, Frade JG, Eiros J, Crespo MS, Fernández N. The unfolded protein response and the phosphorylations of activating transcription factor 2 in the trans-activation of il23a promoter produced by β-glucans. J Biol Chem 2014; 289:22942-22957. [PMID: 24982422 DOI: 10.1074/jbc.m113.522656] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Current views on the control of IL-23 production focus on the regulation of il23a, the gene encoding IL-23 p19, by NF-κB in combination with other transcription factors. C/EBP homologous protein (CHOP), X2-Box-binding protein 1 (XBP1), activator protein 1 (AP1), SMAD, CCAAT/enhancer-binding protein (C/EBPβ), and cAMP-response element-binding protein (CREB) have been involved in response to LPS, but no data are available regarding the mechanism triggered by the fungal mimic and β-glucan-containing stimulus zymosan, which produces IL-23 and to a low extent the related cytokine IL-12 p70. Zymosan induced the mobilization of CHOP from the nuclear fractions to phagocytic vesicles. Hypha-forming Candida also induced the nuclear disappearance of CHOP. Assay of transcription factor binding to the il23a promoter showed an increase of Thr(P)-71-Thr(P)-69-activating transcription factor 2 (ATF2) binding in response to zymosan. PKC and PKA/mitogen- and stress-activated kinase inhibitors down-regulated Thr(P)-71-ATF2 binding to the il23a promoter and il23a mRNA expression. Consistent with the current concept of complementary phosphorylations on N-terminal Thr-71 and Thr-69 of ATF2 by ERK and p38 MAPK, MEK, and p38 MAPK inhibitors blunted Thr(P)-69-ATF2 binding. Knockdown of atf2 mRNA with siRNA correlated with inhibition of il23a mRNA, but it did not affect the expression of il12/23b and il10 mRNA. These data indicate the following: (i) zymosan decreases nuclear proapoptotic CHOP, most likely by promoting its accumulation in phagocytic vesicles; (ii) zymosan-induced il23a mRNA expression is best explained through coordinated κB- and ATF2-dependent transcription; and (iii) il23a expression relies on complementary phosphorylation of ATF2 on Thr-69 and Thr-71 dependent on PKC and MAPK activities.
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Affiliation(s)
- Mario Rodríguez
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valladolid, 47005-Valladolid
| | - Esther Domingo
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas, 47003-Valladolid
| | - Sara Alonso
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas, 47003-Valladolid
| | - Javier García Frade
- Division of Hematology, Hospital Universitario Rio Hortega, 47012-Valladolid, and
| | - José Eiros
- Division of Microbiology, Hospital Universitario Rio Hortega, 47012-Valladolid, Spain
| | - Mariano Sánchez Crespo
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas, 47003-Valladolid,.
| | - Nieves Fernández
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valladolid, 47005-Valladolid
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89
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Ambrose RL, Mackenzie JM. Flaviviral regulation of the unfolded protein response: can stress be beneficial? Future Virol 2013. [DOI: 10.2217/fvl.13.100] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Members of the Flaviviridae family remain some of the most significant human viral pathogens, with few vaccines or antivirals commercially available for therapeutic use. Thus, understanding the intracellular events of replication and how these viruses modulate signaling within an infected cell is of great importance. The ER is central to replication within the Flaviviridae family, as the site of viral protein translation and processing, as a source of membranes for replication complex formation and as a site of virus assembly. This places a large burden upon the organelle, resulting in the induction of ER stress responses, in particular the unfolded protein response. In turn, unfolded protein response signaling induced in infected cells is tightly modulated by the virus in order to maintain an optimal environment for replication. The loss of various components of the stress response can have either beneficial or detrimental effects, presenting intriguing targets for antiviral discovery.
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Affiliation(s)
- Rebecca L Ambrose
- Department of Microbiology & Immunology, University of Melbourne, Parkville, Melbourne, VIC, 3052, Australia
| | - Jason M Mackenzie
- Department of Microbiology & Immunology, University of Melbourne, Parkville, Melbourne, VIC, 3052, Australia
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90
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Hetz C, Chevet E, Harding HP. Targeting the unfolded protein response in disease. Nat Rev Drug Discov 2013; 12:703-19. [DOI: 10.1038/nrd3976] [Citation(s) in RCA: 683] [Impact Index Per Article: 62.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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91
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Meyer F, Ehlers E, Steadman A, Waterbury T, Cao M, Zhang L. TLR-TRIF pathway enhances the expression of KSHV replication and transcription activator. J Biol Chem 2013; 288:20435-42. [PMID: 23723066 PMCID: PMC3711309 DOI: 10.1074/jbc.m113.487421] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Indexed: 11/06/2022] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) is a human γ-herpesvirus. KSHV replication and transcription activator (RTA) is necessary and sufficient for KSHV reactivation from latency. Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns, act through adaptors, and initiate innate and adaptive immune responses against pathogens. Toll/interleukin-1-receptor domain containing adaptor protein inducing interferon-β (TRIF) is an adaptor associated with TLR3 and TLR4 signaling, and is closely related to antiviral signaling to activate type I interferon (IFN) production. We previously found that KSHV RTA degrades TRIF indirectly and blocks TLR3 pathways. In this report, we find that TRIF, as well as TLR3 activation, enhances KSHV RTA protein expression. The C-terminal region of the RTA is involved in the responding TRIF-mediated enhancement. The degradation of TRIF and the enhancement of RTA expression are using two different pathways. The enhancement by TLR-TRIF is at least partially via promoting translational efficiency of RTA mRNA. Finally, the receptor-interacting protein 1 (RIP1) may be involved in TRIF-mediated enhancement of RTA expression, but not in the RTA-mediated degradation of TRIF. Therefore, the activation of TLR-TRIF pathway enhances KSHV RTA protein expression, and KSHV RTA in turn degrades TRIF to block innate immunity. The putative KSHV-TLR-adaptor-interacting loop may be a critical element to evade and usurp host innate immunity in KSHV life-cycle.
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Affiliation(s)
| | | | | | | | | | - Luwen Zhang
- From the School of Biological Sciences and
- the Nebraska Center for Virology, University of Nebraska, Lincoln, Nebraska 68583
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92
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Sano R, Reed JC. ER stress-induced cell death mechanisms. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:3460-3470. [PMID: 23850759 DOI: 10.1016/j.bbamcr.2013.06.028] [Citation(s) in RCA: 1437] [Impact Index Per Article: 130.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 06/24/2013] [Accepted: 06/26/2013] [Indexed: 02/07/2023]
Abstract
The endoplasmic-reticulum (ER) stress response constitutes a cellular process that is triggered by a variety of conditions that disturb folding of proteins in the ER. Eukaryotic cells have developed an evolutionarily conserved adaptive mechanism, the unfolded protein response (UPR), which aims to clear unfolded proteins and restore ER homeostasis. In cases where ER stress cannot be reversed, cellular functions deteriorate, often leading to cell death. Accumulating evidence implicates ER stress-induced cellular dysfunction and cell death as major contributors to many diseases, making modulators of ER stress pathways potentially attractive targets for therapeutics discovery. Here, we summarize recent advances in understanding the diversity of molecular mechanisms that govern ER stress signaling in health and disease. This article is part of a Special Section entitled: Cell Death Pathways.
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Affiliation(s)
- Renata Sano
- Sanford-Burnham Medical Research Institute, La Jolla, CA, 92037, USA
| | - John C Reed
- Sanford-Burnham Medical Research Institute, La Jolla, CA, 92037, USA.
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93
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FGF-2 prevents cancer cells from ER stress-mediated apoptosis via enhancing proteasome-mediated Nck degradation. Biochem J 2013; 452:139-45. [PMID: 23448571 DOI: 10.1042/bj20121671] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Induction of ER (endoplasmic reticulum) stress-mediated apoptosis in cancer cells represents an alternative approach for cancer therapy. Whether FGF-2 (fibroblast growth factor 2)-induced survival signals may interact with ER stress signalling in cancer cells remains elusive. In the present study, we showed that pretreatment with FGF-2 decreased the inhibition of DNA synthesis and induction of apoptosis by two different ER stress inducers, TM (tunicamycin) and TG (thapsigargin), in both human hepatoblastoma HepG2 cells and breast cancer MCF-7 cells. Pretreatment with FGF-2 prevented ER stress-mediated apoptosis by decreasing ER stress-induced CHOP [C/EBP (CCAAT/enhancer-binding protein)-homologous protein] expression. We further demonstrated that pretreatment with FGF-2 mediated the decrease in TM-induced CHOP expression and apoptosis through ERK1/2 (extracellular-signal-regulated kinases 1 and 2) pathway. Finally, we demonstrated that FGF-2 promoted proteasome-mediated degradation of Nck (non-catalytic region of tyrosine kinase adaptor protein), an SH (Src homology) 2/SH3-containing adaptor protein. Whereas overexpression of Nck1 decreased FGF-2-induced ERK1/2 phosphorylation to inhibit the effect of FGF-2 on TM-induced CHOP expression and apoptosis, a decrease in Nck expression prevented TM-induced CHOP expression and apoptosis. Taken together, the findings of the present study provide the first evidence that Nck plays a pivotal role in integrating FGF-2 and ER stress signals to counteract the ER stress deleterious effect on cancer cell survival.
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94
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Maurel M, Chevet E. Endoplasmic reticulum stress signaling: the microRNA connection. Am J Physiol Cell Physiol 2013; 304:C1117-26. [DOI: 10.1152/ajpcell.00061.2013] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The endoplasmic reticulum (ER)-induced unfolded protein response (ERUPR) is an adaptive mechanism that is activated upon accumulation of misfolded proteins in the ER and aims at restoring ER homeostasis. The ERUPR is transduced by three major ER-resident stress sensors, namely PKR-like endoplasmic reticulum kinase (PERK), activating transcription factor 6 (ATF6), and inositol requiring enzyme 1 (IRE1). Activation of these ER stress sensors leads to transcriptional reprogramming of the cells. Recently, microRNAs (miRNAs), small noncoding RNAs that generally repress gene expression, have emerged as key regulators of ER homeostasis and important players in ERUPR-dependent signaling. Moreover, the miRNAs biogenesis machinery appears to also be regulated upon ER stress. Herein we extensively review the relationships existing between “canonical” ERUPR signaling, control of ER homeostasis, and miRNAs. We reveal an intricate signaling network that might confer specificity and selectivity to the ERUPR in tissue- or stress-dependent fashion. We discuss these issues in the context of the physiological and pathophysiological roles of ERUPR signaling.
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Affiliation(s)
- Marion Maurel
- INSERM U1053, Bordeaux, France; and
- Université Bordeaux-Segalen, Bordeaux, France
| | - Eric Chevet
- INSERM U1053, Bordeaux, France; and
- Université Bordeaux-Segalen, Bordeaux, France
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95
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Sidrauski C, Acosta-Alvear D, Khoutorsky A, Vedantham P, Hearn BR, Li H, Gamache K, Gallagher CM, Ang KKH, Wilson C, Okreglak V, Ashkenazi A, Hann B, Nader K, Arkin MR, Renslo AR, Sonenberg N, Walter P. Pharmacological brake-release of mRNA translation enhances cognitive memory. eLife 2013; 2:e00498. [PMID: 23741617 PMCID: PMC3667625 DOI: 10.7554/elife.00498] [Citation(s) in RCA: 460] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 04/23/2013] [Indexed: 12/13/2022] Open
Abstract
Phosphorylation of the α-subunit of initiation factor 2 (eIF2) controls protein synthesis by a conserved mechanism. In metazoa, distinct stress conditions activate different eIF2α kinases (PERK, PKR, GCN2, and HRI) that converge on phosphorylating a unique serine in eIF2α. This collection of signaling pathways is termed the 'integrated stress response' (ISR). eIF2α phosphorylation diminishes protein synthesis, while allowing preferential translation of some mRNAs. Starting with a cell-based screen for inhibitors of PERK signaling, we identified a small molecule, named ISRIB, that potently (IC50 = 5 nM) reverses the effects of eIF2α phosphorylation. ISRIB reduces the viability of cells subjected to PERK-activation by chronic endoplasmic reticulum stress. eIF2α phosphorylation is implicated in memory consolidation. Remarkably, ISRIB-treated mice display significant enhancement in spatial and fear-associated learning. Thus, memory consolidation is inherently limited by the ISR, and ISRIB releases this brake. As such, ISRIB promises to contribute to our understanding and treatment of cognitive disorders. DOI:http://dx.doi.org/10.7554/eLife.00498.001.
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Affiliation(s)
- Carmela Sidrauski
- Department of Biochemistry and Biophysics , University of California, San Francisco , San Francisco , United States ; Howard Hughes Medical Institute, University of California, San Francisco , San Francisco , United States
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96
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Benosman S, Ravanan P, Correa RG, Hou YC, Yu M, Gulen MF, Li X, Thomas J, Cuddy M, Matsuzawa Y, Sano R, Diaz P, Matsuzawa SI, Reed JC. Interleukin-1 receptor-associated kinase-2 (IRAK2) is a critical mediator of endoplasmic reticulum (ER) stress signaling. PLoS One 2013; 8:e64256. [PMID: 23724040 PMCID: PMC3665826 DOI: 10.1371/journal.pone.0064256] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 04/12/2013] [Indexed: 12/11/2022] Open
Abstract
Endoplasmic reticulum (ER) stress occurs when unfolded proteins accumulate in the lumen of the organelle, triggering signal transduction events that contribute either to cellular adaptation and recovery or alternatively to cellular dysfunction and death. ER stress has been implicated in numerous diseases. To identify novel modulators of ER stress, we undertook a siRNA library screen of the kinome, revealing Interleukin-1 Receptor-Associated Kinase-2 (IRAK2) as a contributor to unfolded protein response (UPR) signaling and ER stress-induced cell death. Knocking down expression of IRAK2 (but not IRAK1) in cultured mammalian cells suppresses ER stress-induced expression of the pro-apoptotic transcription factor CHOP and activation of stress kinases. Similarly, RNAi-mediated silencing of the IRAK family member Tube (but not Pelle) suppresses activation of stress kinase signaling induced by ER stress in Drosophila cells. The action of IRAK2 maps to the IRE1 pathway, rather than the PERK or ATF6 components of the UPR. Interestingly, ER stress also induces IRAK2 gene expression in an IRE1/XBP1-dependent manner, suggesting a mutually supporting amplification loop involving IRAK2 and IRE1. In vivo, ER stress induces Irak2 expression in mice. Moreover, Irak2 gene knockout mice display defects in ER stress-induced CHOP expression and IRE1 pathway signaling. These findings demonstrate an unexpected linkage of the innate immunity machinery to UPR signaling, revealing IRAK2 as a novel amplifier of the IRE1 pathway.
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Affiliation(s)
- Samir Benosman
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Palaniyandi Ravanan
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Ricardo G. Correa
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Ying-Chen Hou
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Minjia Yu
- The Cleveland Clinic Foundation, Department of Immunology, Lerner Research Institute (NB30), Cleveland, Ohio, United States of America
| | - Muhammet Fatih Gulen
- The Cleveland Clinic Foundation, Department of Immunology, Lerner Research Institute (NB30), Cleveland, Ohio, United States of America
| | - Xiaoxia Li
- The Cleveland Clinic Foundation, Department of Immunology, Lerner Research Institute (NB30), Cleveland, Ohio, United States of America
| | - James Thomas
- University of Texas, Southwestern Medical Center, Dallas, Texas, United States of America
| | - Michael Cuddy
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Yasuko Matsuzawa
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Renata Sano
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Paul Diaz
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Shu-ichi Matsuzawa
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - John C. Reed
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
- * E-mail:
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97
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Cláudio N, Dalet A, Gatti E, Pierre P. Mapping the crossroads of immune activation and cellular stress response pathways. EMBO J 2013; 32:1214-24. [PMID: 23584529 DOI: 10.1038/emboj.2013.80] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 03/15/2013] [Indexed: 12/14/2022] Open
Abstract
The innate immune cell network detects specific microbes and damages to cell integrity in order to coordinate and polarize the immune response against invading pathogens. In recent years, a cross-talk between microbial-sensing pathways and endoplasmic reticulum (ER) homeostasis has been discovered and have attracted the attention of many researchers from the inflammation field. Abnormal accumulation of proteins in the ER can be seen as a sign of cellular malfunction and triggers a collection of conserved emergency rescue pathways. These signalling cascades, which increase ER homeostasis and favour cell survival, are collectively known as the unfolded protein response (UPR). The induction or activation by microbial stimuli of several molecules linked to the ER stress response pathway have led to the conclusion that microbe sensing by immunocytes is generally associated with an UPR, which serves as a signal amplification cascade favouring inflammatory cytokines production. Induction of the UPR alone was shown to promote inflammation in different cellular and pathological models. Here we discuss how the innate immune and ER-signalling pathways intersect. Moreover, we propose that the induction of UPR-related molecules by microbial products does not necessarily reflect ER stress, but instead is an integral part of a specific transcription programme controlled by innate immunity receptors.
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Affiliation(s)
- Nuno Cláudio
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, UM2, Marseille, France
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98
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Abstract
The respiratory tract has a surface area of approximately 70 m(2) that is in direct contact with the external environment. Approximately 12,000 l of air are inhaled daily, exposing the airway epithelium to up to 25 million particles an hour. Several inhaled environmental triggers, like cigarette smoke, diesel exhaust, or allergens, are known inducers of endoplasmatic reticulum (ER) stress and cause a dysregulation in ER homeostasis. Furthermore, some epithelial cell types along the respiratory tract have a secretory function, producing large amounts of mucus or pulmonary surfactant, as well as innate host defense molecules like defensins. To keep up with their secretory demands, these cells must rely on the appropriate functioning and folding capacity of the ER, and they are particularly more vulnerable to conditions of unresolved ER stress. In the lung interstitium, triggering of ER stress pathways has a major impact on the functioning of vascular smooth muscle cells and fibroblasts, causing aberrant dedifferentiation and proliferation. Given the large amounts of foreign material inhaled, the lung is densely populated by various types of immune cells specialized in engulfing and killing pathogens and in secreting cytokines/chemokines for efficient microbial clearance. Unfolded protein response signaling cascades have been shown to intersect with the functioning of immune cells at all levels. The current review aims to highlight the role of ER stress in health and disease in the lung, focusing on its impact on different structural and inflammatory cell types.
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99
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Changes in translational control after pro-apoptotic stress. Int J Mol Sci 2012; 14:177-90. [PMID: 23344027 PMCID: PMC3565257 DOI: 10.3390/ijms14010177] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 11/06/2012] [Accepted: 12/10/2012] [Indexed: 01/17/2023] Open
Abstract
In stressed cells, a general decrease in the rate of protein synthesis occurs due to modifications in the activity of translation initiation factors. Compelling data now indicate that these changes also permit a selective post-transcriptional expression of proteins necessary for either cell survival or completion of apoptosis when cells are exposed to severe or prolonged stress. In this review, we summarize the modifications that inhibit the activity of the main canonical translation initiation factors, and the data explaining how certain mRNAs encoding proteins involved in either cell survival or apoptosis can be selectively translated.
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100
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Abstract
By controlling gene expression at the level of mRNA translation, organisms temporally and spatially respond swiftly to an ever-changing array of environmental conditions. This capacity for rapid response is ideally suited for mobilizing host defenses and coordinating innate responses to infection. Not surprisingly, a growing list of pathogenic microbes target host mRNA translation for inhibition. Infection with bacteria, protozoa, viruses, and fungi has the capacity to interfere with ongoing host protein synthesis and thereby trigger and/or suppress powerful innate responses. This review discusses how diverse pathogens manipulate the host translation machinery and the impact of these interactions on infection biology and the immune response.
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Affiliation(s)
- Ian Mohr
- Department of Microbiology, NYU Cancer Institute, New York University School of Medicine, New York, NY 10016, USA
| | - Nahum Sonenberg
- Department of Biochemistry, Goodman Cancer Centre, McGill University, Montreal, QC H3A 1A3, Canada
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